1. Technical Field
The method and apparatus of this invention relate generally to tire operations. More specifically, it relates to an apparatus and method for assisting in the lifting of tires onto and off of a truck bed and for providing a safety cage during the inflation of tires.
Currently, separate pieces of equipment are required for providing a means of retaining tires while being placed onto or removed from a truck bed and for providing the safety cage feature required by the Environmental Protection Agency during inflation of tires. Consequently, there is a need for a single piece of equipment which may perform both functions and yet be capable of compact storage when the device is not in use.
2. Description of the Prior Art
Prior art devices for retaining tires in a stationary position while being loaded onto or from truck beds and devices for providing the required safety cage feature during inflation are well known in the art. However, prior to the present invention, two separate pieces of equipment were required to perform these two functions.
In one common prior art device, front and back inverted V-shaped channels spanning the width of a truck lift gate are secured thereto. A large pivotal U-shaped support arm is hinged at one end of the lift gate and pivots from the horizontal to a substantially vertical, over-center position. For the loading/unloading function, the U-shaped support arm is pivoted upward to the over-center position. Tires are then placed against the U-shaped support arm and between the two inverted V-shaped channels such that the tire rests against the U-shaped support arm and is prevented from rolling forward and backward by the inverted V-shaped channels. A major disadvantage with this configuration, is that the U-shaped support arm does not fold down into the inverted V-shaped channels. Consequently, the operator must step over a double height obstruction in order to get into and out of the truck bed. Additionally, with this type of a prior art configuration, an additional separate piece of safety equipment is required.
The Environmental Protection Agency regulations require that a tire-servicing truck be equipped with a safety cage for use during inflation of tires. The purpose of such a safety cage is to prevent injury to the operator in the event that a tire would explode during the inflation operation. A conventional configuration for such a safety cage is two U-shaped halves pivotally connected by means of a hinge at the top of the halves. This additional piece of equipment must then be stored separately in the bed of the truck with the obvious disadvantage that the safety cage takes up additional valuable space in the bed of the truck. Additionally, the safety cage must be removed and replaced from the bed of the truck each time a tire is to be inflated. This difficult task is made doubly difficult by the aforementioned fact that the U-shaped support arm folded onto the V-shaped channels presents a doubly high barrier for the operator to climb over when getting into and out of the truck bed.
Additional examples of prior art tire handling devices are provided in the Black U.S. Pat. No. 3,850,295 and Slonim U.S. Pat. No. 3,405,665. Black discloses a tire shipping and storage structure for maintaining one or more stacks of tires in compressed mode during shipping and storage. Slonim discloses a shipping palett also for use in shipping and transporting or storing goods. Neither Black nor Slonim makes any mention of use on a truck bed for facilitating the placing of tires into the truck bed or removing them therefrom. Additionally, there is no indication that the units may be compactly stowed during periods of non-use nor that the devices may be used for the EPA-mandated safety cage during the inflation process.
Therefore, a primary objective of the present invention is to provide an apparatus which may function as both the mandated safety cage and as a support apparatus facilitating the loading and removal of tires onto and from a truck bed.
Another objective of the present invention is to provide a tire support apparatus which is capable of being compactly stored when not in use.
Another objective of the present invention is to provide a safety cage apparatus which is capable of protecting the operator and preventing injury in the event of an explosion during inflation, as required by the Environmental Protection Agency rules.
Another objective of the present invention is to provide a combination safety cage and tire support apparatus which may be easily and quickly converted from the safety cage mode of operation to the tire support mode of operation.
Another objective of the present invention is to provide a combination safety cage and tire support apparatus which may be used on any truck lift gate.
Another objective of the present invention is to provide a combination safety cage and tire support apparatus which may be secured to the lift gate of a vehicle thereby preventing the apparatus from being left at the job site.
Another objective of the present invention is to provide a combination safety cage and tire support apparatus capable of being adjusted in size to accommodate tires of various sizes.
Another objective of the present invention is to provide a combination safety cage and tire support apparatus having locking means for locking the apparatus into the proper position.